1. Field of the Invention
The present invention relates, in general, to lifts for vehicles, and in particular, to low-rise surface lifts for vehicles.
2. Description of the Related Art
Establishments or shops where vehicles, such as cars, trucks, and the like, are serviced often need to raise the vehicles from the surface of the shop floor to facilitate the tasks to be performed by a service attendant or mechanic. In many applications, such as vehicle body repair, tire rotation, brake servicing, as well as new and used vehicle preparation and reconditioning, the desired height that a vehicle must be lifted is quite limited, i.e., only to the waist or chest of the repair person. For such applications, use of a "low-rise" surface-mounted lift, as distinguished from a hydraulic lift with a below-ground buried lifting cylinder, is well-known. Such surface-mounted low-rise lifts are typically bolted to the surface of the floor of a service bay in a garage.
At least two varieties of surface-mounted lifts employing a low-rise parallelogram design are well-known. The first variety has adjustable arms and pads for contact with the undercarriage of a vehicle. A representative well-known example of such a surface-mounted low-rise lift is the model PAL7 surface-mounted low-rise parallelogram lift manufactured and sold for many years by Rotary Lift Company, Memphis, Tenn. The PAL7 lift is designed with parallel front and rear supporting legs pivotally attached to a base and a superstructure, with a hydraulic cylinder that raises and lowers the superstructure and associated vehicle support arms.
A second variety of surface-mounted lift employing a low-rise parallelogram design has no adjustable arms and pads, but instead has four fixed pads, one pair forward and one pair rearward, attached to a superstructure that can be raised and lowered. Such a lift is typically used in high-volume tire stores or brake maintenance facilities, and allows faster operation than a lift with adjustable arms and pads that must be correctly positioned for each vehicle. A representative well-known example of this second variety lift is the model PFX surface-mounted low-rise parallelogram lift manufactured and sold for many years by Rotary Lift Company, Memphis, Tenn. The PFX lift is designed with parallel front and rear supporting legs pivotally attached to a base and a superstructure, with a hydraulic cylinder that raises and lowers the superstructure and associated fixed pads, attached thereto, that contact the undercarriage or rocker panels of a vehicle.
However, as such surface-mounted lifts are bolted to the floor of the garage bay, their use is limited to "dedicated bay" applications. A significant capital investment, sufficient to outfit each garage bay with its own dedicated and permanently mounted lift, has been heretofore required by the buyer of surface-mounted lifts.
It is therefore desirable to have a portable surface lift for a vehicle that may be easily moved from garage bay to garage bay, as required, thereby reducing the number of surface lifts required by a given establishment, yet which remains stable beneath a vehicle when in use. Rather than requiring wheels to be attached and removed every time the lift is moved, the lift should be able to be moved into place, yet remain safely in position and not move when lifting the vehicle. Preferably, no substantial effort should be required to raise the lift from the garage surface, and the only effort required to transport the lift should be that necessary to overcome the inertia of the lift itself. It is also desirable to have manual towing means removable from the lift for moving the lift from one location to another.